Intraocular pharmacology of antibiotics administered by various routes. We hope to determine the optimal mode of administration of antibiotics in the therapy of bacterial infections of the eye, especially endophthalmitis using rabbits and squirrel monkeys. Four modes of local delivery will be used: (a) subconjunctival; (b) retrobulbar; (c) intravitreal injection; and (d) continuous slow-release perfusion. In addition, the effect of concomitant systemic therapy will be compared for each of the modes of local therapy. At varying intervals the eyes will be removed and dissected and the tissues assayed for antibiotic by disc-agar diffusion bioassay and radioassay. The significance of antibiotic accumulation in ocular tissues. We hope to determine the extent of binding of clindamycin and gentamicin by ocular tissues of pigmented and albino rabbits in vivo, and the proportions of antibiotic that are "readily available" or "tightly-bound" at different intervals; to assess whether or not this accumulation has the characteristics of "binding" (saturability and competitive inhibition of uptake); and to examine the effects of these differences on therapeutic activity in vivo.